Diesel additive, preparation method and usage method thereof

ABSTRACT

The present invention relates to a fuel additive. The fuel additive comprises 70-90 wt. % of a nonylphenol polyether amine, 10-30 wt. % of a multi-amido polyisobutylene amine, and 0-20 wt. % of an auxiliary additive based on the total weight of the fuel additive. The fuel additive provided by the present disclosure is able to effectively remove carbon deposits at a gas intake valve and a combustion chamber of a fuel engine.

FIELD OF THE INVENTION

The present disclosure relates to a fuel additive, in particular, to a fuel additive which can be used to remove carbon deposits at a gas intake valve and a combustion chamber of a fuel engine.

BACKGROUND OF THE INVENTION

The working temperature of the gas intake valve of the automobile fuel engine is about 170-180° C., and at this temperature, the olefins contained in the fuel (especially gasoline) may undergo oxidation because of its instability, which produces the carbon deposits in gum form. The carbon deposits attach to the inside of the gas intake valve, thus affecting the working efficiency of the gas intake valve.

The working temperature of the combustion chamber of the automobile fuel engine is about 250-600° C., and at this temperature, the aromatic hydrocarbon contained in the fuel (especially gasoline) may generate carbon deposits from combustion, which can deposit in the combustion chamber. When the total amount of the carbon deposits in the combustion chamber of the fuel engine increases, it may cause the compression ratio of the fuel engine to increase, and make it difficult for heat to dissipate, thus at the end of the compression in the combustion chamber, the gas temperature rises, the octane value requirement increases, and when serious, it may increase the mechanical interference between the piston top and cylinder head of the fuel engine combustion chamber and generate the phenomenon, of “carbon cylinder-knocking” which results in increased consumption of engine oil.

Currently, some fuel additives in the industry have been separately used to remove the carbon deposits attached to the gas intake valve and the combustion chamber of the fuel engine.

SUMMARY OF THE INVENTION

The present disclosure provides a fuel additive which can not only be used to remove the carbon deposits at the gas intake valve of the fuel engine, but also can be used to remove the carbon deposits at the combustion chamber of the fuel engine.

Certain aspects of the present disclosure provide a fuel additive, which comprises 70-90 wt. % of a nonylphenol polyether amine, 10-30 wt. % of a multi-amido polyisobutylene amine, and 0-20 wt. % of an auxiliary additive, based on the total weight of the fuel additive.

Certain aspects of the present disclosure provide a method for preparing the fuel additive, which comprises the step of mixing the ingredients of the fuel additive according to the present disclosure.

Certain aspects of the present disclosure provide a method for using the fuel additive, which comprises the step of adding the fuel additive according to the present disclosure into a fuel.

The fuel additive provided by the present disclosure is able to effectively remove the carbon deposits at the gas intake valve and the combustion chamber of the fuel engine.

DETAILED DESCRIPTION

It should be understood that without departing from the scope or spirit of the present disclosure, the persons skilled in the art can conceive other various embodiments according to the teachings of this specification and can modify them. Therefore, the following embodiment are not to be construed in a limiting sense.

Unless otherwise indicated, all numbers used in this specification and claims for expressing the sizes, quantities and physicochemical properties of features should be understood as in all cases to be modified by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters listed in the foregoing specification and attached claims are all approximations, and the persons skilled in the art can use the teachings disclosed herein it appropriately change these approximations for seeking the desired properties. The use of numerical range represented by endpoints includes all numbers within that range and any sub-range within that range, e.g., 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4 and 5, and so on.

Fuel Additive

According to certain embodiments, the fuel additive provided by the present disclosure comprises: 70-90 wt. % of nonylphenol polyether amine, 10-30 wt. % of multi-amido polyisobutylene amine, and 0-20 wt. % of auxiliary additive, based on the total weight of the fuel additive.

Nonylphenol Polyether Amine

In the fuel additive, the nonylphenol polyether amine helps to remove the carbon deposits of a fuel engine (for example, the carbon deposits at the gas intake valve of a gasoline engine). The polar amine group in the nonylphenol polyether amine can be adsorbed to the metal surface of the fuel engine, while the structure of the nonylphenol is relatively similar to that of the carbon deposits, so the carbon deposits attached to the metal surface of the fuel engine (for example, the inside of the gas intake valve and the inside surface of the combustion chamber) can be stripped down and dispersed into small particles, which are then burned off in the combustion chamber.

According to certain embodiments, the nonylphenol polyether amine comprises the following general formula:

Wherein, m=1-2, n=24-26, y=1-2.

According to certain embodiments, the nonylphenol polyether amine has a molecular weight of 1000-2000.

According to certain embodiments, the nonylphenol polyether amine is present at a level of 70-90 wt. %, based on the total weight of the fuel additive. According to certain embodiments, the nonylphenol polyether amine is present at a level of 80-90 wt. %, based on the total weight of the fuel additive. When the polyether amine is present at a level of 70-90 wt. %, the fuel additive is not only able to effectively remove the carbon deposits at gas intake valve of the fuel engine, but also able to effectively remove the carbon deposits in the combustion chamber of the fuel engine.

According to certain embodiments, the nonylphenol polyether amine may be selected from FL-1000 or PEA-PEO which are commercially available from Huntsman Corporation.

Multi-Amido Polyisobutylene Amine

In the fuel additive, the multi-amido polyisobutylene amine can synergistically coordinate with the polyether amine in certain proportion to improve the ability of the fuel additive to remove the carbon deposits of the combustion chamber.

According to the conventional art, the industry generally believes that polyisobutylene amine (PIBA) has relatively high viscosity, high thermal stability, and is difficult to decompose at high temperature. Adding polyisobutylene amine into fuel may cause polyisobutylene amine to be adsorbed onto the surface or the combustion chamber and then participate in the generation of the carbon deposits in the combustion chamber. However, the present disclosure inventors have surprisingly found that the fuel additive obtained by making multi-amido polyisobutylene amine coordinate with the polyether amine in a certain proportion can effectively remove the carbon deposits in the combustion chamber.

The multi-amido polyisobutylene amine has the general formula of:

Wherein, R₁, R₂ and R₃ are each independently selected from one of the group consisting of: H, CH₃, C₂H₅, C₃H₇ and C₄H₉ , n=4-18, m=2-5.

According to certain embodiments, the multi-amido polyisobutylene amine has a molecular weight of 800-1200.

According to certain embodiments, the multi-amido polyisobutylene amine comprises at least one of a diamine polyisobutylene amine and a penta-amine polyisobutylene amine.

According to certain embodiments, the multi-amido polyisobutylene amine is present at a level of 10-30 wt. %, based on the total weight of the fuel additive. According to certain embodiments, the multi-amido polyisobutylene amine is present at a level of 10-20 wt. %, based on the total weight of the fuel additive. When the multi-amido polyisobutylene amine is present at a level of 10-30 wt. %, the fuel additive is not only able to effectively remove the carbon deposits at gas intake valve of the fuel engine, but also able to effectively remove the carbon deposits in the combustion chamber of the fuel engine.

According to certain embodiments, the multi-amido polyisobutylene amine may be selected from 1018A or 1018S which are commercially available from QingYuanXing Company.

Auxiliary Additive

The additive can comprise at least one of a diluent and a friction modifier.

In the fuel additive, the diluent helps to reduce the viscosity of the fuel additive. According to certain embodiments, the diluent may comprise at least one of a saturated straight-chain hydrocarbon solvent, a cycloalkanes solvent, and a mixed aromatic hydrocarbon agent.

According to certain embodiments, the diluent is present at a level of 0-20 wt. %, based on the total weight of the fuel additive. According to certain embodiments, the diluent is present at a level of 5-20 wt. %, based on the total weight of the fuel additive.

According to certain embodiments, the diluent may be D60 which is commercially available from ExxonMobil Company.

In the fuel additive, the friction modifier helps to reduce the friction of the inner surface of the engine. According to certain embodiments, the friction modifier can comprise at least one of a glyceryl monooleate and a polyester. According to certain embodiments, the friction modifier is present at a level of 0-10 wt. %, based on the total weight of the fuel additive. According to certain embodiments, the friction modifier is present at a level of 5-10 wt. %, based on the total weight of the fuel additive.

According to certain embodiments, the friction modifier may be 9525A which is commercially available from Lubrizol Company.

The Method For Preparing the Fuel Additive

According to certain embodiments, the ingredients of the fuel additive according the present disclosure can be mixed together to obtain the fuel additive. The description about each ingredient of the fuel additive can be found in the “Fuel Additive” section of the present description.

According to certain embodiments, the ingredients used to prepare the fuel additive can be added to a stainless steel vessel and mixed under normal temperature (about 25° C.) and normal pressure (about 1 atm) to obtain the fuel additive.

The Method For Using the Fuel Additive

According to certain embodiments, the fuel additive according to the present disclosure can be added into the fuel. According to certain embodiments, under normal temperature (about 25° C.) and normal pressure (about 1 atm), the fuel additive can be added into the fuel in a proportion of 1:1000-1:2000. The description about the fuel additive can be found in the “Fuel Additive” section of the present description.

According to certain embodiments (preferably), the fuel includes gasoline. According to certain embodiments, the gasoline incudes at least one of 92# gasoline, 95# gasoline and ethanol gasoline.

The following embodiments are intended to describe the present disclosure illustratively rather then restrictively.

Embodiment 1 is a fuel additive, which comprises 70-90 wt. % of the nonylphenol polyether amine, 10-30 wt. % of the multi-amido polyisobutylene amine, and 0-20 wt. % of the additive, based on the total weight of the fuel additive.

Embodiment 2 is the fuel additive according to Embodiment 1, wherein the nonylphenol polyether amine comprises the following general formula:

wherein, m=1-2, n=24-26, y=1-2.

Embodiment 3 is the fuel additive according to Embodiment 1 or 2, wherein the nonylphenol polyether amine has a molecular weight of 1000-2000.

Embodiment 4 is the fuel additive according to any one of the Embodiments 1 to 3, wherein the nonylphenol polyether amine is present at a level of 80-90 wt. %.

Embodiment 5 is the fuel additive according to any one of the Embodiments 1 to 4, wherein the multi-amido polyisobutylene amine comprises the following general formula:

wherein, R₁, R₂ and R₃ are each independently selected from one of the group consisting of: H, CH₃, C₂H₅, C₃H₇ and C₄H₉, n=4-18, m=2-5.

Embodiment 6 is the fuel additive according to any one of the Embodiments 1 to 5, wherein the multi-amido polyisobutylene amine is the polyisobutylene amine of the following structural formula with a molecular weight of 800-1200.

Embodiment 7 is the fuel additive according to any one of the Embodiments 1 to 6, wherein the multi-amido polyisobutylene amine includes: at least one of a nomo-amine polyisobutylene amine and a penta polyamine polyisobutylene amine.

Embodiment 8 is the fuel additive according to any one of the Embodiments 1 to 7, wherein the multi-amido polyisobutylene amine is present at a level of 10-20 wt. %.

Embodiment 9 is the fuel additive according to any one of the Embodiments 1 to 8, wherein the additive comprises at least one of a diluent and a friction modifier.

Embodiment 10 is the fuel additive according to any one of the Embodiments 1 to 9, wherein the additive is present at a level of 5-50 wt. %.

Embodiment 11 is a method for preparing the fuel additive, comprising the step of mixing the ingredients of the fuel additive according to any one of Embodiments 1 to 10.

Embodiment 12 is a method for using the fuel additive, comprising the step of adding the fuel additive according to any one of Embodiments 1 to 10 into a fuel.

Embodiment 13 is the method according to Embodiment 12, wherein the fuel is gasoline.

EXAMPLES

The following Examples and comparative Examples are used to help understand the present invention, but the scope of the present invention should not be understood as being limited to the following specific Examples and Comparative Examples. Unless otherwise indicated, all parts and percentages are based on weight.

Preparation of the Fuel Additive

Under normal temperature (about 25° C.) and normal pressure (about 1 atm), the ingredients of the fuel additive were added to a stainless steel container and mixed to obtain the fuel additive.

Adding the fuel additive into the fuel

Under normal temperature (about 25° C.) and normal pressure (about 1 atm), the fuel additive was added into the fuel (for example, gasoline) in a proportion of 1:1000.

The trade names, functions, chemical names and manufacturers of the ingredients used to produce the fuel additives of the Examples and Comparative Examples of the present disclosure are listed in the following table 1a.

TABLE 1a Physical and Trade chemical Name Ingredient characteristic Manufacturer FL-1000 Nonylphenol Molecular weight is Huntsman Chemical polyether amine about 1000 Trading Co., Ltd. PEA-PEO Nonylphenol Molecular weight is Huntsman Chemical polyether amine about 2000 Trading Co., Ltd. PIBA Polyisobutene Molecular weight is BASF China Co., amine about 1200 Ltd. 1018C Diamino Molecular weight is Qingyuanxing polyisobutene about 800 Chemical amine Technology Co. Ltd. 1018S Penta polyamino Molecular weight is Qingyuanxing polyisobutene about 800 Chemical amine Technology Co. Ltd. 1018T Penta polyamino Molecular weight is Qingyuanxing polyisobutene about 1200 Chemical amine Technology Co. Ltd. D60 Diluent Hydrocarbon solvent Exxon Mobil with the flash point Chemical Co. Ltd. of about 60° C. 9525A Friction Complex of various Lubrizol Special modifiers esters Chemicals Manufacturing (Shanghai) Co., Ltd.

Test Method

In the present disclosure, “fuel engine gas intake valve carbon deposit removal rate test” is used to measure the capability of the fuel additives provided by the present disclosure to remove the carbon deposits at the gas intake valve of the fuel engine.

In the present disclosure, “fuel engine combustion chamber carbon deposit removal rate test” is used to measure the capability of the fuel additives provided by the present disclosure to remove the carbon deposits in the combustion chamber of the fuel engine.

The test reagents and test equipment involved in “fuel engine gas intake valve carbon deposit removal rate test” and “fuel engine combustion chamber carbon deposit removal rate test” are listed in the following table 1b.

TABLE 1b Test reagent or test equipment Manufacturer N-heptane (AR) Sinopharm Chemical Reagent Co., Ltd. Petroleum ether (AR) Jiangsu Yonghua Fine Chemicals Co., Ltd. Anhydrous ethanol (AR) Sinopharm Chemical Reagent Co., Ltd. Cyclopentadiene Lanzhou Victory Petrochemical Company 93# gasoline China Petroleum and National Gas Co., Ltd L-2 type gasoline engine deposit Lanzhou Victory Petrochemical simulation test machine Company Balance (accurate color 0.1 mg) Mettler Toledo Instruments (Shanghai) Co., Ltd. Dryer (with color changing silica gel desiccant) Oven (with temperature controlled Thermo Fisher Science and at 100 ±2 ° C.) Technology (China) Co., Ltd. Micro-injector (accurate to 1 ml) Lanzhou Victory Petrochemical Company Volametric flask (300 ml) Lanzhou Victory Petrochemical Company Thermometer (accurate to 0.1° C.) Lanzhou Victory Petrochemical Company

Fuel Engine Gas Valve Carbon Deposit Removal Rate Test

-   1. Preparation of the Carbon Deposit Collector     -   1.1 The carbon deposit collector (an aluminium plate with 10 cm         length and 8 cm width) was soaked in anhydrous ethanol for 60         minutes, until its surface was bright and had no stains. Then         the carbon deposit collector was cleaned with running water and         then soaked in anhydrous ethanol for 5 minutes, and then taken         out with a tweezer and placed into an oven at 100° C. to dry for         not less than 15 minutes.     -   1.2 The carbon deposit collector was taken out of the oven and         placed into a desiccator to cool down to room temperature (about         25° C.).     -   1.3 After the carbon deposit collector was cool, its temperature         was measured with a thermometer and recorded. The mass of the         carbon deposit collector was recorded and the carbon deposit         collector was placed into a desiccator for use (as noted, it         should be ensured that in this step, the temperature change of         the carbon deposit collector between two consecutive weighings         was not more than 0.2° C., and the weighing inaccuracy deviation         was less than 0.2 mg). -   2. Preparation of the Fuel Sample and the Fuel Additive     -   2.1 300 ml of 93# gasoline was sampled and poured info flask 1;     -   2.2 Under normal temperature (about 25° C.) and normal pressure         (about 1 atm), 300 ml of fuel additive was poured into flask 2. -   3. Generation of Gasoline Deposits     -   3.1 The time of the test time-meter was set to 70 minutes, and         the 300 ml of 93# gasoline sample in the flask 1 was added into         the sample bottle of L-2 type gasoline engine deposit simulation         test machine, and then 0.6 ml of cyclopentadiene was added.     -   3.2 The carbon deposit collector was loaded into the bracket         slot of this simulation test machine, so that the carbon deposit         collector could point to the nozzle of the simulation test         machine. The temperature measuring thermocouple was plugged.     -   3.3 The power of the simulation lest machine was turned on, and         its heating switch was started, so that the temperature of the         carbon deposit collector could reach 170° C. to simulate the         working environment of the fuel engine gas intake valve.     -   3.4 The air shut-off valve of this simulation test machine was         opened, the gas pressure was adjusted to 80±0.5 kPa, and the         flow was controlled in a steady state (700±50 L/hr).     -   3.5 The fuel shut-off valve of the simulation test machine was         opened, the oil pressure was adjusted to 7.5±0.5 kPa, the fuel         flowmeter regulating valve was opened, and the flow was         controlled in a steady state (4±1 ml/min).     -   3.6 Fuel injection starts, and the switch of the time-meter was         turned on to start timing.     -   3.7 The temperature of the carbon deposit collector was         maintained at 170-180° C., until the injection of 93# gasoline         oil sample was completely finished, then the fuel injection         device and the switch of the time-meter were closed.     -   3.8 The temperature of the carbon deposit collector was         maintained at 170-180° C. for 10 minutes, and the heating switch         was closed, so that the temperature was reduced below 50° C.         naturally.     -   3.9 The temperature measuring thermocouple of the carbon deposit         collector was taken out.     -   3.10 The carbon deposit collector was taken out, and it was         soaked in a beaker filled with n-heptane for 1 minute, and then         it was taken out.     -   3.11 The carbon deposit collector was immersed in a beaker         filled with petroleum ether, and taken out after soaking for 1         min, and then placed into a 100° C. oven for not less than 15         minutes.     -   3.12 The carbon deposit collector was taken out from the oven         and cooled to room temperature (about 25° C.) in a desiccator.     -   3.13 The temperature of the carbon deposit collector was         measured. If the inaccuracy deviation between the temperature         measured at this moment and the temperature measured before the         test was less than 0.2° C., then the carbon deposit collector         could be weighed.     -   3.14 The calculation formula for the carbon deposit formation         amount at the fuel engine gas intake valve is:

m=m ₁ −m ₀   (formula 1)

In the formula:

-   -   m represents the mass of the carbon deposit formed during the         test, and the unit is mg;     -   m₁ represents the final mass of the carbon deposit collector in         the test, and the unit is mg;     -   m₀ represents the initial mass of the carbon deposit collector         in the test, and the unit is mg;

-   4. Removal of the Carbon Deposits at the Fuel Engine Gas Intake     Valve     -   4.1 The time of the test time-meter was set, and the 300 ml of         fuel additive in the flask 2 was added into the sample bottle of         L-2 type gasoline engine deposit simulation test machine.     -   4.2 The carbon deposit collector fully dried in the step 3.12         was loaded into this bracket slot of the simulation test         machine, so that the carbon deposit collector could point to the         nozzle of the simulation test machine. The temperature measuring         thermocouple was plugged.     -   4.3 The power of the simulation test machine was turned on, and         its heating switch was started, so that the temperature of the         carbon deposit collector could reach 170-180° C. to simulate the         working environment of the fuel engine gas intake value.     -   4.4 The air shut-off valve of this simulation test machine was         opened, the gas pressure was adjusted to 80±0.5 kPa, and the         flow was controlled in a steady state (700±50 L/hr).     -   4.5 The fuel shut-off valve of this simulation test machine was         opened, the oil pressure was adjusted to 7.5±0.5 kPa, the fuel         flow-meter regulating valve was opened, and the flow was         controlled in a steady state (4±1 ml/min).     -   4.6 Fuel injection starts, and the switch of the time-meter was         turned on to start timing.     -   4.7 The temperature of the carbon deposit collector was         maintained at the 170-180° C. until the injection of 93#         gasoline oil sample was completely finished, then the fuel         injection device and the switch of the time-meter were closed.     -   4.8 The temperature of the carbon deposit collector was         maintained at 170-180° C. for 10 minutes, and the heating switch         was closed, so that the temperature was reduced below 50° C.         naturally.     -   4.9 The temperature measuring thermocouple of the carbon deposit         collector was taken out.     -   4.10 The carbon deposit collector was taken out, and it was         soaked in a beaker filled with n-heptane, and then taken out.     -   4.11 The carbon deposit collector was immersed in a beaker         filled with petroleum ether, and taken out after soaking for 1         min, and then placed into a 100° C. oven for not less than 15         minutes.     -   4.12 The carbon deposit collector was taken out from the oven         and cooled to room temperature (about 25° C.) in a desiccator.     -   4.13 The temperature of the carbon deposit collector was         measured. If the inaccuracy deviation between the temperature         measured at this moment and the temperature measured before the         test was less than 0.2° C., then the carbon deposit collector         could be weighed.     -   4.14 The calculation formula for carbon deposit removal rate of         the fuel engine gas intake valve is:

δ1=[(m−m ₂)/m]×100%   (formula 2)

In the formula:

-   -   δ1 represents the carbon deposit removal rate of the fuel engine         gas intake valve, and the unit is %;     -   m represents the mass of the carbon deposits formed by the 93#         gasoline during the test, and the unit is mg;     -   m₂ represents the final mass of the carbon deposit collector in         the test, and the unit is mg.

Fuel engine combustion chamber carbon deposit removal rate test

“Automobile combustion chamber carbon deposit removal rate test” was carried out with the same method and steps as “Fuel engine gas intake valve carbon deposit removal rate test”, except that:

In step 3.3, the temperature of the carbon deposit collector should reach 250° C. to simulate the working environment of the fuel engine combustion chamber.

In step 3.7, 3.8, 3.3 and 3.8, the temperature of the carbon deposit collector should be 250° C.

In step 3.14, the calculation formula of the carbon deposit formation amount of the gasoline combustion chamber is:

n=n ₁ −n ₀   (formula 3)

In the formula:

-   -   n represents the mass of the carbon deposits formed during the         test, and the unit is mg;     -   n₁ represents the final mass of the carbon deposit collector in         the test, and the unit is mg;     -   n₀ represents the initial mass of the carbon deposit collector         in the test, and the unit is mg.

In step 4.14, the calculation formula of the carbon deposit removal rate of the fuel engine combustion chamber is:

δ2=[(n−n ₂)/n]×100%   (formula 4)

In the formula:

-   -   δ2 represents the carbon deposit removal rate of the fuel engine         combustion chamber, and the unit is %;     -   n represents the mass of the carbon deposits formed by the 93#         gasoline during the test, and the unit is mg;     -   n₂ represents the final mass of the carbon deposit collector in         the test, and the unit is mg.

Examples 1 to 7

According to the method described above and on the base of the formulation listed in Table 2 (the values listed in Table 2 are all based on weight percentage), under the conditions of normal temperature (25° C.) and normal pressure (about 1 atm), the ingredients of the fuel additives were added to a stainless steel container and mixed to obtain the fuel additives 1 to 7.

According to the method described above, the fuel engine gas intake valve carbon deposit removal rates and the fuel engine combustion chamber carbon deposit removal rates of the fuel additives 1 to 7 were tested and the results were listed in Table 3.

Comparative Examples C1 to C3

According to the method described above and on the basis of the formulation listed in Table 2 (the values listed in Table 2 are all based on weight percentage), under the conditions of normal temperature (25° C.) and normal pressure (about 1 atm), the ingredients of the fuel additives were added to a stainless steel container and mixed to obtain the fuel additives C1 in C3.

According to the method described above, the fuel engine gas intake valve carbon deposit removal rate and the fuel engine combustion chamber carbon deposit removal rate of the fuel additives C1 to C3 were tested and the results are listed in Table 3.

TABLE 2 FL-1000 PEA-PEO PIBA 1018C 1018S 1018T D60 9525A (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) Example 1  70 — — — 30 — — — Example 2  80 — — — 20 — — — Example 3  90 — — — 10 — — — Example 4  85 — — 15 — — — — Example 5  85 — — — — 15 — — Example 6 — 85 — — 15 — — — Example 7  80 — — — 13 — 5 2 Comparative 100 — — — — — — — Example C1 Comparative — — 100 — — — — — Example C2 Comparative  90  10 Example C3

TABLE 3 Fuel engine gas intake Fuel engine combustion valve carbon deposit chamber carbon deposit removal rateδ₁ (%) removal rateδ₂ (%) Example 1 99.0 51.2 Example 2 98.9 60.3 Example 3 99.1 55.6 Example 4 99.3 57.2 Example 5 98.7 56.2 Example 6 99.1 56.2 Example 7 99.1 55.6 Comparative 99.2 31.4 Example C1 Comparative 67.3 −3.2 Example C2 (The negative value represents, relative to its mass before the test, the final mass of the carbon deposit collector is increased during the test) Comparative 98.2 27.7 Example C3

According to the Examples 1-7, because the fuel additives provided by the present disclosure comprise 70-90 wt. % of a nonylphenol polyether amine and 10-30 wt. % of a multi-amido polyisobutylene amine, these fuel additives are not only able to effectively remove the carbon deposits at gas intake valve of the fuel engine, but also able to effectively remove the carbon deposits in the combustion chamber of the fuel engine.

According to the Examples 2-7, when the fuel additives comprise 80-90 wt. % of a nonylphenol polyether amine and 10-20 wt. % of a multi-amido polyisobutylene amine, the fuel additives provided by the present disclosure are particularly able to effectively remove the carbon deposits in the combustion chamber of the fuel engine (δ2 is greater than 55%).

According to the Comparative Example C1, when the fuel additive comprises the nonylphenol polyether amine only, but does not contain the multi-amido polyisobutylene amine, this fuel additive lacks the ability to remove the carbon deposits in the combustion chamber of the fuel engine.

According to the Comparative Example C2, when the fuel additive comprises the multi-amido polyisobutylene amine only, this fuel additive lacks the ability to remove the carbon deposits at the gas intake valve and the combustion chamber of the fuel engine.

According to the Comparative Example C3, when the fuel additive comprises the nonylphenol polyether amine and the polyisobutylene amine, but does not contain the multi-amido polyisobutylene amine, this fuel additive lacks the ability to remove the carbon deposits in the combustion chamber of the fuel engine.

In summary, the fuel additives according to the present disclosure, are not only able to effectively remove the carbon deposits at gas intake valve of the fuel engine, but also able to effectively remove the carbon deposits in the combustion chamber of the fuel engine.

Although for purposes of illustration, the Embodiments described above contain many specific details, but the ordinary skilled person in the art will appreciate that many variations, modifications, substitutions and changes of such details all fall into the scope of the present disclosure which is protected by the claims. Therefore, the disclosure described in the Embodiments does not make any restriction in the present disclosure which is protected by the claims. The appropriate scope of the present disclosure should be defined by the claims and the appropriate legal equivalents. All cited references are incorporated herein by reference at its entirety. 

1. A fuel additive, comprising: 70-90 wt. % of a nonylphenol polyether amine; 10-30 wt. % of a multi-amido polyisobutylene amine; and 0-20 wt. % of an auxiliary additive, based on the total weight of the fuel additive.
 2. The fuel additive according to claim 1, wherein the nonylphenol polyether amine includes the following general formula:

wherein, m=1-2, n=24-26, y=1-2.
 3. The fuel additive according to claim 2, wherein the nonylphenol polyether amine has a molecular weight of 1000-2000.
 4. The fuel additive according to claim 1, wherein the nonylphenol polyether amine is present at a level of 80-90 wt. %.
 5. The fuel additive according to claim 1, wherein the multi-amido polyisobutylene amine comprises the following general formula:

wherein, R₁, R₂ and R₃ are each independently selected from one of the group consisting of: H, CH₃, C₂H₅, C₃H₇ and C₄H₉, n=4-18, m=2-5.
 6. The fuel additive according to claim 5, wherein the multi-amido polyisobutylene amine has a molecular weight of 800-1200.
 7. The fuel additive according to claim 1, wherein the multi-amido polyisobutylene amine comprises at least one of a diamine polyisobutylene amine and a penta-amine polyisobutylene amine.
 8. The fuel additive according to claim 1, wherein the multi-amido polyisobutylene amine is present at a level of 10-20 wt. %.
 9. The fuel additive according to claim 1, wherein the auxiliary additive comprises at least one of a diluent and a friction modifier.
 10. The fuel additive according to claim 1, wherein the auxiliary additive is present at a level of 5-20 wt. %.
 11. A method for preparing the fuel additive, comprising the step of mixing the ingredients of the fuel additive according to claim
 1. 12. A method of using the fuel additive, comprising the step of adding the fuel additive according to claim 1 into a fuel.
 13. The method according to claim 11, wherein the fuel is gasoline. 